1. Technical Field
Exemplary embodiments relate generally to an electronic device. More particularly, embodiments of the inventive concept relate to an electronic device having a touch-screen unit, a method of operating the electronic device, and a computer-readable medium that stores a program.
2. Description of the Related Art
Recently, an electronic device having a touch-screen unit (e.g., a cellular phone, a smart-phone, a smart-pad, a laptop, a computer, a television, etc) is widely used. Thus, various user interfaces have been suggested for those electronic devices. According to a typical user interface employed in the electronic device, a multi-touch operation (i.e., an operation in which a distance between two points of the touch-screen unit is adjusted while the two points of the touch-screen unit are touched by a user) is mainly performed when the user inputs a user command such as an image zoom-in command, an image zoom-out command, etc. For example, the user may input the image zoom-in command by increasing a distance between two points of the touch-screen unit (i.e., by pulling the two points of the touch-screen unit apart to enlarge a size of the image) while touching the two points of the touch-screen unit. On the other hand, the user may input the image zoom-out command by decreasing a distance between two points of the touch-screen unit (i.e., by squeezing the two points of the touch-screen unit to reduce a size of the image) while touching the two points of the touch-screen unit. However, since the multi-touch operation is required for the user to use two fingers or two hands, the multi-touch operation may be inconvenience for user as a size of the electronic device gets bigger.